The invention relates generally to a fiber optic cable guide to permit bendable installation of optical fiber cables and a method of application of the guide to a cable. More particularly, the invention is directed to a fiber optic cable guide that is removably attachable to a connector subassembly disposed at an end of the fiber optic cable and to a related method.
Often a fiber optic cable is terminated in a constrained enclosure such as a small cabinet or elsewhere where space is otherwise limited. Sometimes a fiber optic cable is required to bend through about ninety degrees shortly after the termination point. If appropriate care is not given the cable, the bending of the cable may violate the minimum bend radius of the optical fiber, which could lead to attenuation and even breakage of the optical fiber in the cable. Various types of guides have been developed for bendably connecting fiber optic cables to other components without violating the minimum bend radius of the fiber optic cable. For example, guides are available such as those shown in U.S. Pat. Nos. 6,134,370; 5,710,851; 5,640,476; 5,347,603; and 5,037,175.
However, these guide devices include various disadvantages, such as bulkiness that may preclude their use in some applications, especially where small connectors or tight spaces are involved. Also, some of these devices cover most or all of the cable within the bend, making it difficult or impossible to visually detect which cable (for example, according to its color or markings) extends into a given connector. This difficulty can be increased where a large number of cables are connected in a group or where the connected cables extend out of sight beyond the guide. Some of the above guides also must be installed prior to the connector being installed on the optical fiber. Also, some of these devices include the guide as a permanent part of the connector itself, such as incorporating the guide into the boot, thereby precluding the ability to selectively provide a non-guided (i.e., non-bending) connector in the field. Some of these devices are also not readily rotatable relative to the connector after attachment to the connector, thereby limiting installation flexibility. Finally, the devices do not provide for a simple and reliable removal of a cable from the guide, either by choice or in case of an inadvertent snagging of a cable.
A fiber optic cable guide is disclosed for removable placement on a connectorized fiber optic cable assembly having a fiber optic cable and at least one connector subassembly. The fiber optic cable has a minimum bend radius. The fiber optic cable guide includes an elongated member at least partially curved along its length with a radius of curvature not less than the minimum bend radius of the fiber optic cable for guiding the fiber optic cable in a desired direction. The elongated member has a first end, a second end, a middle section between the first and second ends, and a channel extending from the first end to the second end for receiving the fiber optic cable. The first end is configured to be removably disposed around a portion of the connector subassembly. The second end includes at least one primary securement element extending from the second end and configured to releasably hold at least the fiber optic cable to the elongated member. The middle section includes at least one secondary securement element extending from the middle section and configured to releasably hold at least the fiber optic cable to the elongated member. The primary securement element is configured so that the fiber optic cable is releasable from the primary-securement element upon pulling the fiber optic cable at a first predetermined force in a direction generally away from a bottom of the channel.
The secondary securement element may be configured so that the fiber optic cable is releasable from the secondary securement element upon pulling of the fiber optic cable at a second predetermined force in the direction generally away from the bottom of the channel. The second predetermined force may be greater than the first predetermined force, or the second predetermined force may be substantially equal to the first predetermined force.
The at least one primary securement element may extend arcuately over a portion of the channel, and the second end may include at least two primary securement elements. The at least two primary securement elements may be disposed at two different axial positions along the second end of the elongated member, or the at least two primary securement elements may be disposed opposite each other at a common axial position along the second end of the elongated member, thereby forming a substantially C-shape with the second end.
The connector subassembly may include a strain relief boot, and the at least one primary securement element may be configured to hold the elongated member to the strain relief boot. The first end of the elongated member may be configured to allow the elongated member to rotate 360 degrees relative to the connector subassembly. The first end of the elongated member may have a receptacle extending from the first end, the receptacle defining a longitudinally-extending channel therethrough and a longitudinally-extending slot in communication with the channel. The receptacle may be substantially C-shaped. The slot may be configured to allow the fiber optic cable to be slid radially therethrough. If connector subassembly includes a strain relief boot, the receptacle may be configured to be removably disposed around the boot.
The at least one secondary securement element may be configured to allow axial movement of the fiber optic cable relative to the elongated member, or may be configured to be crimpable around the fiber optic cable to thereby substantially preclude axial movement of the fiber optic cable relative to the elongated member.
The middle section may have at least two secondary securement elements, which may be disposed at two different axial positions along the middle section of the elongated member, or which may be disposed opposite each other at a common axial position along the middle section end of the elongated member, thereby forming a substantially C-shape with the middle section. The at least one secondary securement element may also extend across a center of the channel.
The elongated member may be curved through about 90 degrees, and the channel may have a width that decreases in the direction of the first end to the second end.
Also, the elongated member may include at least one stiffening element. If desired, two ribs extending along the elongated member may be provided for stiffening. The stiffening element may be disposed proximate the secondary securement element or proximate an opening through the elongated member.
According to another aspect of the invention, a fiber optic cable guide is disclosed for removable placement on a connectorized fiber optic cable assembly having a fiber optic cable and at least one connector subassembly. The fiber optic cable has a minimum bend radius. The fiber optic cable guide includes an elongated member at least partially curved along its length with a radius of curvature not less than the minimum bend radius of the fiber optic cable for guiding the fiber optic cable in a desired direction. The elongated member has a first end, a second end, a middle section between the first and second ends, and a channel extending from the first end to the second end for receiving the fiber optic cable. The first end includes a substantially C-shaped receptacle for releasably holding a portion of the connector subassembly. The second end includes two primary securement elements extending from the second end to releasably hold at least the fiber optic cable. The middle section includes one secondary securement element extending from the middle section to releasably hold at least the fiber optic cable. The primary securement elements are configured so that the fiber optic cable is releasable from the primary securement elements upon pulling the fiber optic cable in a direction generally away from a bottom of the channel.
According to another aspect of the invention, a fiber optic cable guide is disclosed for removable placement on a connectorized fiber optic cable assembly having a fiber optic cable and at least one connector subassembly including a strain relief boot. The fiber optic cable has a minimum bend radius. The fiber optic cable guide includes an elongated member curved along its length with a radius of curvature not less than the minimum bend radius of the fiber optic cable. The elongated member has a first end, a second end, a middle section between the first and second ends, and a channel extending from the first end to the second end for receiving the fiber optic cable and the strain relief boot. The first end is removably attached to the strain relief boot. The second end includes at least one primary securement element extending from the second end to releasably hold the fiber optic cable to the elongated member substantially within the channel. The primary securement element is configured so that the fiber optic cable is releasable from the primary securement element upon pulling the fiber optic cable in a direction away from a bottom of the channel.
The elongated member may be forked. Each connector subassembly may include a strain relief boot and each receptacle may be disposed around a respective strain relief boot. The elongated member may include two channels extending from the first end to the second end, each channel for receiving a respective fiber optic cable. The primary securement elements may be configured so that the respective fiber optic cables are releasable upon pulling of the fiber optic cable in a direction away from a bottom of the respective channel. A middle section may be included between the first and second ends and two secondary securement elements disposed on the middle section, each secondary securement element for holding a respective fiber optic cable.
According to another aspect of the invention, a method is disclosed of removably fixing a fiber optic cable in a curvature not greater than that defined by a minimum bend radius of the fiber optic cable, a connector subassembly being disposed at at least one end of the fiber optic cable. The method includes the steps of radially inserting the fiber optic cable into a first end of a guide member, the first end being configured to be disposed around a portion of the connector subassembly, the guide member being at least partially curved along its length with a radius of curvature not less than the minimum bend radius and defining a channel for receiving the fiber optic cable extending from the first end of the guide member to a second end of the guide member, and radially inserting the fiber optic cable in a direction toward the bottom of the channel past at least one securement element extending from the guide member spaced from the first end to hold the fiber optic cable to the guide member.
Further steps may include inserting the fiber optic cable past at least another securement element axially spaced from the at least one securement element, crimping one of the securement elements over the fiber optic cable, axially sliding the guide member along the fiber optic cable after the first radially inserting step, removing the fiber optic cable from the guide member by pulling the cable radially from the at least one securement element, or rotating the guide member relative to the fiber optic cable to a desired orientation after the radially inserting steps.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.